1. Field of the Invention
The present invention relates to an improved structure of a Christmas flashing control lamp, and more especially to a three-wire Christmas flashing control lamp.
2. Description of the Prior Art
The prior art Christmas light string is formed by a two-wire flashing control lamp 10 electrically connected with a series of regular lamps 11, as shown in FIG. 1. An electric power source is then supplied to the Christmas light string via an electric plug 2. The flashing control lamp 10 includes a bimetal plate therein. The illumination of the light string is controlled by the heating state of the bimetal plate in the flashing control lamp.
Referring to FIG. 2, a perspective view of the prior art two-wire flashing control lamp 10 is shown. The two-wire flashing control lamp 10 includes two conductive poles 12 and 13 which are connected with exterior conductive wires. A filament 14 is connected between two ends of the conductive poles 12 and 13. A bimetal plate 15 having a lower free end is connected with the first conductive pole 12. When the conductive poles 12 and 13 are supplied with an electric power source, the filament 14 is heated. After a predetermined time is reached, the lower free end of the heated bimetal plate 15 will bend to contact with the second conductive pole 13 so that the two conductive poles 12 and 13 will short to bypass the electric current flow through the filament 14. At this time, the temperature in the lamp will be cooled down.
After the temperature within the bulb has decreased to a predetermined level, the bimetal plate 15 will return to the original state. Therefore, by means of the aforementioned switching operation, the flickering effect of the light string may be controlled. However, in the circuit of this prior art Christmas light string, the light string can only create a monotonous flashing effect without various flickering patterns. Therefore, it is necessary to provide a three-wire Christmas flashing control lamp which has contact switching function so that the light string can achieve a various flickering effect.
Accordingly, the object of the present invention is to provide a three-wire flashing control lamp structure of Christmas lamps, wherein by the structure of the three-wire flashing control lamp matches a simple circuit design and arrangement, the diversified flickering effects can be presented.
The present invention will be better understood and its numerous objects and advantages will become apparent to those skilled in the art by reference to the following drawings in which: